SpaceX's prototype Grasshopper rocket took one giant leap last week, rising to a 12-story height and settling back down safely on its landing legs at the company's Texas rocket test facility. Just for fun, the engineers let a dummy cowboy go along for the ride.

"To provide a little perspective on the size of Grasshopper, we added a 6-ft cowboy to the rocket. ... Then we took him for a ride," Musk wrote. So how did the cowboy fare? "No problemo," said Musk.

The 10-story-tall Grasshopper rocket is designed to take off and land vertically, as part of Musk's plan to develop a rocket capable of returning itself to a launch pad for rapid reusability. Today's vertical-takeoff launch systems generally rely upon expendable lower stages — although the space shuttle's solid rocket boosters could be recovered from the Atlantic Ocean and refurbished for reuse. If a rocket stage can return to its launch facility intact and ready to go again, that could significantly lower the cost of spaceflight. That's what Musk is shooting for.

SpaceX says the Grasshopper consists of a Falcon 9 rocket first stage, a Merlin 1D engine, four steel landing legs with hydraulic dampers, and a steel support structure. During the prototype's first flight test on Sept. 21, the Grasshopper rose 6 feet into the air. The second test, on Nov. 1, lasted 8 seconds and lifted the Grasshopper 17.7 feet (5.4 meters) off the pad. The company said last week's third test went for 29 seconds, during which the Grasshopper rose 131 feet (40 meters) into the air, hovered and landed safely back on the pad, using closed-loop thrust vector and throttle control.

SpaceX

A dummy cowboy is perched on SpaceX's Grasshopper rocket for a Dec. 17 test.